Headline
CVE-2023-25165: Merge pull request from GHSA-pwcw-6f5g-gxf8 · helm/helm@5abcf74
Helm is a tool that streamlines installing and managing Kubernetes applications.getHostByName is a Helm template function introduced in Helm v3. The function is able to accept a hostname and return an IP address for that hostname. To get the IP address the function performs a DNS lookup. The DNS lookup happens when used with helm install|upgrade|template or when the Helm SDK is used to render a chart. Information passed into the chart can be disclosed to the DNS servers used to lookup the IP address. For example, a malicious chart could inject getHostByName into a chart in order to disclose values to a malicious DNS server. The issue has been fixed in Helm 3.11.1. Prior to using a chart with Helm verify the getHostByName function is not being used in a template to disclose any information you do not want passed to DNS servers.
@@ -18,6 +18,7 @@ package engine
import ( “fmt” “path” “strings” “sync” “testing” @@ -89,6 +90,7 @@ func TestRender(t *testing.T) { {Name: "templates/test2", Data: []byte(“{{.Values.global.callme | lower }}”)}, {Name: "templates/test3", Data: []byte(“{{.noValue}}”)}, {Name: "templates/test4", Data: []byte(“{{toJson .Values}}”)}, {Name: "templates/test5", Data: []byte(“{{getHostByName \"helm.sh\"}}”)}, }, Values: map[string]interface{}{"outer": "DEFAULT", "inner": "DEFAULT"}, } @@ -117,6 +119,7 @@ func TestRender(t *testing.T) { "moby/templates/test2": "ishmael", "moby/templates/test3": "", "moby/templates/test4": `{"global":{"callme":"Ishmael"},"inner":"inn","outer":"spouter"}`, "moby/templates/test5": "", }
for name, data := range expect { @@ -200,6 +203,42 @@ func TestRenderInternals(t *testing.T) { } }
func TestRenderWIthDNS(t *testing.T) { c := &chart.Chart{ Metadata: &chart.Metadata{ Name: "moby", Version: "1.2.3", }, Templates: []*chart.File{ {Name: "templates/test1", Data: []byte(“{{getHostByName \"helm.sh\"}}”)}, }, Values: map[string]interface{}{}, }
vals := map[string]interface{}{ "Values": map[string]interface{}{}, }
v, err := chartutil.CoalesceValues(c, vals) if err != nil { t.Fatalf("Failed to coalesce values: %s", err) }
var e Engine e.EnableDNS = true out, err := e.Render(c, v) if err != nil { t.Errorf("Failed to render templates: %s", err) }
for _, val := range c.Templates { fp := path.Join("moby", val.Name) if out[fp] == “” { t.Errorf("Expected IP address, got %q", out[fp]) } } }
func TestParallelRenderInternals(t *testing.T) { // Make sure that we can use one Engine to run parallel template renders. e := new(Engine)
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Red Hat Security Advisory 2023-1326-01 - Red Hat OpenShift Container Platform is Red Hat's cloud computing Kubernetes application platform solution designed for on-premise or private cloud deployments. This advisory contains the container images for Red Hat OpenShift Container Platform 4.13.0. Issues addressed include bypass, denial of service, information leakage, out of bounds read, and remote SQL injection vulnerabilities.
Red Hat OpenShift Container Platform release 4.13.0 is now available with updates to packages and images that fix several bugs and add enhancements. This release includes a security update for Red Hat OpenShift Container Platform 4.13. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2021-4235: A flaw was found in go-yaml. This issue occurs due to unbounded alias chasing, where a maliciously crafted YAML file can cause the system to consume significant system resources. If p...
A Helm contributor discovered an information disclosure vulnerability using the `getHostByName` template function. ### Impact `getHostByName` is a Helm template function introduced in Helm v3. The function is able to accept a hostname and return an IP address for that hostname. To get the IP address the function performs a DNS lookup. The DNS lookup happens when used with `helm install|upgrade|template` or when the Helm SDK is used to render a chart. Information passed into the chart can be disclosed to the DNS servers used to lookup the IP address. For example, a malicious chart could inject `getHostByName` into a chart in order to disclose values to a malicious DNS server. ### Patches The issue has been fixed in Helm 3.11.1. ### Workarounds Prior to using a chart with Helm verify the `getHostByName` function is not being used in a template to disclose any information you do not want passed to DNS servers. ### For more information Helm's security policy is spelled out in deta...